1. Field of the Invention
This invention relates to extraction cleaning. In one of its aspects, the invention relates to an upright extraction cleaning machine with enhanced surface cleaning. In another of its aspects, the invention relates to an extraction cleaning machine with a heated cleaning solution. In yet another of its aspect, the invention relates to a method of surface cleaning with surface heating.
2. Description of the Related Art
Upright extraction cleaning machines have been used for removing dirt from surfaces such as carpeting and bare floors. The known extraction cleaning machines can be in the form of a canister-type unit, as disclosed in U.S. Pat. No. 5,237,720 to Blase et al., or an upright unit, as disclosed in U.S. Pat. No. 6,131,237 to Kasper, et al.
Either type of unit contains a fluid delivery system for depositing a quantity of cleaning solution on the surface to be cleaned. The cleaning solution dissolves the dirt, removes the dirt from the surface, and places the dirt in suspension, which aids in the vacuum removal of the dirt from the surface. The solubility of the dirt in the cleaning solution can be increased by heating the cleaning solution. The cleaning solution is typically heated with an in-line heater or an immersion heater in a cleaning solution tank prior to being deposited on the surface to be cleaned.
The heated cleaning solution tends to cool during the time that the cleaning solution travels from the in-line heater to the surface to be cleaned. The heating solution is further cooled upon contact with the surface. Additional cooling can take place between the time that the heating solution contacts the surface and the time that the solution and dirt is to be extracted from the surface. This loss of heat can reduce the effectiveness of the cleaning solution.